• Journal of the Korean Society of Radiology
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• v.79 no.5
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• pp.259-263
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• 2018

A 52-year-old male complained of a painless, firm, and slow-growing mass in his right breast outer portion. The chest CT revealed a 3.3 cm-sized oval shaped, microlobulated, mild enhancing mass. Ultrasound showed a microlobulated marginated heterogeneous hypoechoic mass with internal vascularity and calcifications in the mass. On the ultrasound-guided core needle biopsy, the mass was confirmed as a benign granular cell tumor (GCT). The patient transferred to another hospital and underwent surgical removal of the lesion. GCT of the breast is uncommon and mostly benign neoplasm to originate from Schwann cell. Clinical and radiologic features of GCTs, including CT and ultrasound images, mimic malignancy and make diagnosis of GCT more difficult. The CT images of GCTs are much rarely reported. Physicians and radiologists must be aware of radiologic characteristics of this rare benign tumor for male breast, to avoid misdiagnosis this tumor for breast malignancy and overtreat.

• Journal of the Korean earth science society
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• v.43 no.3
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• pp.405-429
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• 2022

Detrital zircon LA-MC-ICP-MS U-Pb dating of the Cretaceous Gurye Group, Gurye Basin, was carried out. Gurye Group consists of Supyeongri, Geumjeongri, Togeum, and Obongsan formations in ascending order, and five samples were collected for age dating. Based on the dating results, the lowermost Supyeongri and the uppermost Obongsan formations show narrow age ranges. Only Precambrian and Late Cretaceous zircons were found in the Supyeongri and Obongsan formations, respectively. However, the upper and lower Geumjeongri, and Togeum formations show wide age ranges from the Precambrian to Cretaceous. The youngest detrital zircon U-Pb ages of each formation except the Supyeongri Formation, which lacks Cretaceous zircon, were calculated to be ca. 107.4 Ma in the lower Geumjeongri Formation, ca. 104.6 Ma in the upper Geumjeongri Formation, ca. 97.7 Ma in the Togeum Formation, and ca. 88.5 Ma in the Obongsan Formation. Such results indicate that the depositional age of the Gurye Group can be constrained from the Lower Cretaceous Albian to the Upper Cretaceous Coniacian. Based on the distribution of the detrital zircon ages from each formation, the source area of the Gurye Group is interpreted to have been extended from the adjacent Youngnam Massif to the Okcheon Belt throughout the basin evolution. The increase of the Cretaceous zircon with time is thought to reflect the slab roll-back of the proto-Pacific plate during the Cretaceous.

• Journal of the Mineralogical Society of Korea
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• v.24 no.4
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• pp.313-320
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• 2011

Mica-type phyllosilicate particles in the shales of the Manhang formation at the Taeback area in the Kangwon Province were studied using electron probe microanalysis (EPMA) and transmission electron microscopy (TEM). The average chemical formula of the mica-type phyllosilicate mineral analysed by EPMA is $K_{1.35}(Fe_{0.18}Mg_{0.03}Al_{3.86})(Si_{6.55}Al_{1.45})O_{20}(OH)_4$. Low K contents compared to the ideal chemistry of muscovite indicate the presence of illite in the mica-type phyllosilicate particle. X-ray diffraction study showed that pyrophyllite commonly coexists with muscovite in the shales from the Manhang Formation. TEM observations showed both the interlayer and intralayer mixing of $9.3-{\AA}$ pyrophyllite and $10-{\AA}$ muscovite layers. The low K content of the mica-type phyllosilicates apparently come from the close mixing of pyrophyllite and muscovite.

• Journal of the Korean Society of Costume
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• v.64 no.1
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• pp.152-164
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• 2014

Korean people have revered the white color and enjoyed wearing white clothes. Various kinds of white clothes have been worn by the Korean people, ranging from everyday wear(便服), and scholar's robe(深衣) for the upper class, to religious costumes like Buddhist monk's robe(僧服), shaman costumes(巫服) and costumes for ancestral rites(祭服), or mourning(喪服). There have been many differing opinions by historians regarding the background of this Baekeuihosang(白衣好尙, the preference for white clothing) tradition and even now, it is frequently being discussed. This study aims to consider and discuss the background of this Baekeuihosang tradition, focusing on Chang-seon Yoo's Baekeuigo(白衣考, the consideration of white clothing), which was published in Dong-A Ilbo in 1934. The purposes of studying literature such as the Baekeuigo is to analyze the arguments on the origin of Baekeuihosang, to analyze Chang-seon Yoo's claim of its origin, and to discuss the culture of Baekeuihosang. Chang-seon Yoo claimed that the existing discussions on the background of Baekeuihosang based on the lack of dyes, or undeveloped technique, economic privation and national control strayed from historical facts, according to literature review. It is not worth discussing the farfetched arguments such as the use of costumes for ancestral rites as everyday wears, or the nation of sorrow. Baekeuihosang tradition mostly originated from the effects of many religions and the taste for innocence, or naturalness. White clothes were infused with the sorrow and emotion of Korean people and were also worn to show resistance to foreign power as symbols of ethnicity. Therefore, there should be a new view of the discussion of white clothes and Korean aesthetic sense, away from the logic distorted by the Japanese colonial view of history.

• Journal of Applied Biological Chemistry
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• v.60 no.2
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• pp.185-190
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• 2017

Antioxidative ability of 50% ethanol extract from leaves of Leucaena leucocephala (Lam.) de Wit was investigated. The extraction yield, total polyphenols and total flavonoids of the ethanol extract were $18.3{\pm}0.40%$, $121.3{\pm}11.04{\mu}g$ gallic acid equivalents/mg and $105.2{\pm}2.77{\mu}g$ quercetin equivalents/mg, respectively. The ethanol extract possessed the antioxidative activities such as free radical, cation radical, and nitrite scavenging activities as well as reducing power and lipid peroxidation inhibitory activity. These antioxidative activities of the ethanol extract increased in proportion to the extract concentration. $EC_{50}$ values for free radical scavenging, cation radical scavenging nitrite scavenging, and reducing power were $133.51{\mu}g/mL$, $667.22{\mu}g/mL$, 2.58 mg/mL, and $250.00{\mu}g/mL$, respectively. Polyphenols and flavonoids are suggested to be the key contributors for the antioxidative ability of the ethanol extract from Leucaena leucocephala leaves.

• Korean Journal of Plant Taxonomy
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• v.48 no.1
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• pp.37-42
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• 2018

A new species, Potentilla baekdusanensis M. Kim, is described here. It is found in Baekdusan Mt., Korea. Potentilla baekdusanensis shares several characteristics (pinnately compound leaves, pubescent leaf blades and leaf petioles, different leaflets size, and absent stolons) with the related species P. fragarioides. However, this new species has small plants with short and curved hairs, 7 leaflets, small lower leaflets, a glabrous leaflet margin, and yellow petals with a reddish yellow base. In contrast, P. fragarioides are large plants with long and straight hairs, 9-15 leaflets, large lower leaflets, a ciliate leaf margin, and yellow petals without a reddish yellow base.

• Journal of Korea Water Resources Association
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• v.47 no.3
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• pp.237-245
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• 2014

Volcanic ash components of Mt. Baekdu were estimated to response the change of water quality environment affected by Mt. Baekdu volcanic ash ejected during eruption. Then the change of water concentrations according to the sedimentation of volcanic ash components were analysed. To estimate volcanic ash components of Mt. Baekdu, similar volcanos were selected through the comparison of main foreign volcano's magma type and the selected volcanic ash components supposed as Baekdu Mountain's. To analyse the change of water concentrations, the change of harmful components affected by volcanic ash sedimentation were analysed and the results were compared with domestic drinking water quality standard. As the result, Al, Cd, F, Fe, Pb, Mg, Cl and Sr could affect to water quality. Among those components, concentrations of Cd, F, Fe, Pb and Mg were estimated to exceed the drinking water quality standard.

• The Journal of the Petrological Society of Korea
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• v.27 no.1
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• pp.17-24
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• 2018

The volcanic history of the volcanic ash cloud movement recorded in the annals of the Choson dynasty in 1654, presumably due to explosive eruptions from Mt. Baekdu volcano. On October 21, 1654, volcanic ash and volcanic gas erupted from Mt. Baekdu could be interpreted as volcanic ash, which was transported to low altitude by winds of north and northeast winds and descended to the south of the peninsula along with volcanic ash clouds. The affected area appeared northward in the southern boundary of Hamgyeongdo, which is estimated to have moved the volcanic ash from Mt. Baekdu to the south of the Korean peninsula. Clouds of volcanic ash have passed through Jeokseong and Jangdan area, Gyeonggido about 500 km away from Mt. Baekdu. This is interpreted as a result of the formation of a volcanic ash cloud along the ground in a curved shape due to the influence of the prevailing wind, which was formed by Plinian-type eruption at Mt. Baekdu. This is reproduced by numerical simulations on the similar weather pattern model.

• Journal of the Mineralogical Society of Korea
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• v.26 no.2
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• pp.111-118
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• 2013

Diagenetic black chert nodules occur in the Paleozoic dolostone in Susan, Jecheon, Korea. They reacted with dolomite to form alteration rim around the nodules during the contact metamorphism probably related to the intrusion of biotite granite. In the earlier stage of alteration, talc and calcite replaced both the chert and dolomite, which were subsequently replaced by tremolite. Significant mass of tremolite occurs along the horizon enriched with chert nodules. Scanning electron microscopy and optical microscopy of the tremolite specimens revealed the elongated morphology of diverse aspect ratios coexisting in several mm scale. Non-asbestiform tremolite columns were also common as well as asbestiform fibrous bundles. Quantitative estimation of asbestos should be more cautious for naturally occurring materials because all the tremolite particles in the outcrop are not asbestiform. The occurrence of asbestiform tremolite in the Susan area indicates that a combination of chert-bearing dolostone, heat source, and aqueous fluids is one of the geological environments for the formation of asbestiform tremolite.

• Journal of The Korean Association of Information Education
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• v.19 no.4
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• pp.409-418
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• 2015

The purpose of this study is derived implications at software curriculum development utilizing the backward design model. In this study, we developed 'Algorithms and Programming' unit teaching plan based on backward design template. First, we have derived enduring understandings, essential questions, specific knowledge and skill on 'Algorithms and Programming' unit by considering the goal, content, achievement standard of Software education operating instructions. Second, we developed authentic tasks using GRASPS technic and holistic scoring rubrics. Third, we developed 7 lesson 14 WHERETO element for effective teaching in 'Algorithms and Programming' unit. Fourth, we investigated about the effectiveness of the development unit based on backward design. Backward design could be useful of developing curriculum unit and lesson plan at software education.